The actor – who played Anakin Skywalker in the Star Wars prequels – admitted his biggest challenge when filming was to stop making those lightsaber noises.

"I had sort of been conditioned, from a very young age, to make the sound effect when I'm swinging a lightsaber," he said at yesterday's (April 14)Star Wars Celebration event. "I know this is something maybe Ewan [McGregor] struggled with a little bit, too, but it was a difficult habit to break."

Christensen explained: "I remember, on a couple of occasions, you would come over after we had filmed a fight scene, and in a very encouraging way, you'd say, 'Hayden, that looks really great, but I can see your mouth moving. You don't have to do that, we add the sound effects in afterward.'